PLMN selection in 5G NR

Hello Experts,

How does UE do PLMN selection in 5G/NR?
Is it the same as 4G?

How does it choose Operator?

Thanks

  1. The UE shall scan all RF channels in the NR bands according to its capabilities to find available PLMNs.

  2. On each carrier, the UE shall search for the strongest cell and read its system information, in order to find out which PLMN(s).

  3. If the UE can read one or several PLMN identities in the strongest cell, each found PLMN shall be reported to the NAS as a high-quality PLMN (but without the RSRP value), provided that the following high-quality criterion is fulfilled.

  4. The search for PLMNs may be stopped on request from the NAS.

  5. The UE may optimise PLMN search by using stored information e.g. frequencies and optionally also information on cell parameters from previously received measurement control information elements

  6. Once the UE has selected a PLMN, the cell selection procedure shall be performed in order to select a suitable cell of that PLMN to camp on.

The UE select (decides) for a particular PLMN after reading SIB1 and getting PLMN information.

In SIB 1 UE read PLMN information for each available MNO like EE, O2, Vodafone or Three (i.e. for UK).

This information can be found in plmn-IndentityList : MCC and MNC

Almost the same, it still follows the same 23.122 procedure. Only difference might be PLMNwact , RAT priority in SIM card with an extra entry for 5G.

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